1. Field of the Invention
The present invention relates generally to water skipping and hydroplaning devices. More particularly, the present invention discloses an advanced and unique water skipping article combining the aspects of a smooth elliptical outer surface and an interior, centrally configured and likewise elliptically shaped cavity or hollow core. While the elliptical outer surface serves to enhance the lift and aerodynamic flight characteristics of the device, the hollowed elliptical inner core creates a gyroscopic effect providing for self righting with increased aeronautical and aerodynamic stability.
2. Description of the Prior Art
The prior art is fairly well documented with examples of water skipping articles and objects. The most basic and earliest type of water skipping device known is a smooth edged and preferably flattened rock or stone, the advantage of which is to provide reasonably level flight trajectory and, hopefully, multiple and individual contact points with the water during skipping.
Attempts have been made in the art to provide a man made, more readily available, and better performing skipping device. One such device is disclosed in U.S. Pat. No. 4,553,758, issued to Zehr, and which teaches a skipping stone formed of a somewhat porous, cementitious material and having a sharply convex peripheral (bulbous lower) edge and a generally cylindrical slightly upwardly converging side wall. The upper surface of the device is generally flat to readily distinguish from its lower water engaging surface. The stone in Zehr is further disclosed as being cast from a mixture of gypsum cement and fine sand and incorporates a radius dimension R and thickness of 0.4 R. A dimpled near-center region extends from the center outwardly about 45% of the radius R.
Glovak U.S. Pat. No. 4,151,997 teaches a hydroplaning disc with a solitary unitary body comprised of aggregated material. The disc is disclosed as being heavier (having a greater density) than the water it displaces and thereby non-floating. A series of longitudinally oriented discontinuities are provided only on the extreme latitudinal periphery of the rim adjacent to the top and bottom surfaces of the disc. The discontinuities exert a greater interfering effect on the airflow and waterflow around the circumference of the disc than over its top and under its bottom. Thus, a turbulent boundary layer is asserted to be created between the layer of air and water and which is alleged to increase the range, frequency of skips and dynamic stability. The bottom of the Glovak article is further disclosed as having a granular texture and which results in a more sure grip and improved hydroplaning stability during skipping motion.
Glovak, U.S. Pat. No. 4,212,462, teaches another type of aerodynamic and hydromechanical hydroplaning disc with a solid unitary body comprised of aggregated material. The disk includes a peripheral edge formed with a top to bottom curvature having a relatively smaller radius at the top than at the bottom and which reduces air resistance while at the same time increasing the planning capacity of the disc as it strikes the water. The texture of the Glovak '462 disk is further such that, in combination with the circular or polygonal edge formations, enhances the aerodynamic, hydrodynamic and hydromechanical characteristics.
Panse U.S. Pat. No. 4,463,954, teaches an aquatic surface skimming (as opposed to skipping or tumbling) projectile and which includes a top, substantially flattened and planar surface and a lower surface including with a frusto-conical shape. The Panse skimming device is disclosed as producing hydrodynamic lift and drag reduction along the water surface and to specifically avoid skipping and tumbling motion.
Finally, Cosmopulus U.S. Pat. No. 4,395,046, teaches a hand thrown game disc for skipping over the surface of water by throwing with a spinning motion and in a generally flat low trajectory. The disc is constructed of a material having a density less than water so that it is floatable thereon. The disc further includes generally auger shaped upper and lower faces (each being oriented in a different direction) and a notch is located in an outer peripheral edge. The auger face is disclosed as providing a lifting motion to the disc and the different auger directions allow the disc to be spun from either hand.